add_index :gpx_files, [:visible, :visibility], :name => "gpx_files_visible_visibility_idx"
remove_index :gpx_files, :name => "gpx_files_visible_public_idx"
remove_column :gpx_files, :public
add_index :gpx_files, [:visible, :visibility], :name => "gpx_files_visible_visibility_idx"
remove_index :gpx_files, :name => "gpx_files_visible_public_idx"
remove_column :gpx_files, :public